UNM Contract Archeology Excavates Mimbres Pit Houses

Beautiful vivid fragments of Mimbres pottery, tiny arrowheads smaller than a fingertip, seeds and bones of animals, metates used to grind corn, rocks chipped and shaped to form the head of a hoe. Those are some of the artifacts students working for the Division of Contract Archeology at UNM are bringing back from southwestern New Mexico this summer.

The project near Lake Roberts in the Gila National Forest is funded by the New Mexico Department of Game and Fish. The department is preparing to repair the dam at Lake Roberts and knew the construction project would likely damage prehistoric Mimbres pit houses in the area, so the Division of Contract Anthropology was hired to survey and excavate the site. The artifacts and the story they tell about the Mimbres people who lived here will be preserved, and eventually put on display.

The sites are from the classic Mimbres period 1000 – 1150 A.D. but may be dated more closely after bits of charcoal collected from hearths at the houses have been carbon-dated. The Mimbres people were part of a larger Mogollon culture, living in the southwest, but their pottery is so distinct that anthropologists have been able to identify them as a separate group living within the larger culture.

Robin Cordero is the staff member in the Division of Contract Archeology who is leading the project. He's also a graduate student working to complete his Ph.D. Cordero says they have been surveying and excavating since May of 2011. Much of the excavation has been completed. Cordero says they've brought back more than 20,000 pieces of chip stone and more than 13,000 pieces of pottery. He says, "Each and every artifact that we bring back has to be washed with a toothbrush and scrubbed to get all of the dirt and the clay off of them. And then all of these big bags of soil that we've brought back have to be washed and processed to get all of the small seeds and all of the really fine pieces of bone and fine little artifacts out."

They have more than 400 pieces of animal bone. Cordero says this will tell them a lot about what the Mimbres people were hunting and eating. He and some of the students will go to the Museum of Southwest Biology on campus this fall to compare and identify their finds with reference samples at the museum. He says they already know the inhabitants of the pit houses were eating fish, deer, rabbits and mice. Cordero says the inhabitants of the pit houses also farmed. In addition to the hoe heads and metates they found, they are also sifting the soil to determine what kind of seeds were a part of their diet.

Some students involved in the excavation will take a ceramics class at UNM this fall, working with Anthropology Professor Patricia Crown who is an expert on pre-historic southwestern pottery. They will do specialized analysis on pottery pieces they helped collect.

At the end of the process, the group will write a report explaining what they learned from the excavation for the NM Department of Game and Fish. That report, minus some detail about the precise location of the site, will then be publicly available.